1. Field of the Invention
The present invention relates to a method of operating a power station plant according to the preamble of claim 1.
2. Discussion of Background
EP-A1-0 462 458 has disclosed a power station plant which essentially comprises a gas-turbine group, a waste-heat steam generator arranged downstream, and an injector system. The components of said gas-turbine group, as an autonomous unit, comprise a generator, a compressor, a combustion chamber and a turbine. The exhaust gases from the turbine are fed to the waste-heat steam generator, where they continue to be utilized in an energetic manner. With the released thermal energy from these exhaust gases, high-pressure steam is generated in a high-pressure part of the waste-heat steam generator, which high-pressure steam is fed to the said injector system and is admitted to the driving nozzle there. Compressed air from the compressor is directed into the receiving nozzle of this injector system: this air is further compressed by the action of the driving nozzle. If the waste-heat steam generator is designed as a dual-pressure boiler, the steam prepared in the low-pressure part is fed, for example, to the combustion chamber. The ultimate purpose of these measures is primarily to minimize the pollutant emissions, in particular the NOx emissions. Besides, the fact of the matter is that, although the specific output of the plant increases, the efficiency gain nonetheless remains relatively modest, so that such a plant does not constitute an alternative to a fully formed combined-cycle plant with regard to efficiency and also specific output.